In roller mills used industrially, a grinding table drives grinding rollers via a grinding bed. In this instance, it is generally necessary to arrange a gearing mechanism below the grinding table. In mills having large throughputs, it is necessary to take into account high investment costs, long procurement times and unsatisfactory availability with such gearing mechanisms.
Therefore, it has already been proposed to drive the grinding rollers in place of the grinding table. If a plurality of grinding rollers are provided, it is thereby possible to distribute the power for driving the roller mill over a corresponding plurality of drives. In that manner, it is possible to use drives which are smaller and therefore cheaper.
In DE 38 01 728 C2 and DE 36 02 932 A1, the complete drive with the motor and gearing mechanism is provided on the pivot lever which retains the grinding roller. Owing to the substantial weight of the drive, increased demands are placed on the bearing of the pivot lever in this embodiment. The motor is further subjected to powerful vibrations owing to the grinding process.
DE 197 02 854 proposes a motor which is fixed in position as an alternative construction type. The drive power is transmitted to the gearing mechanism which is secured to the pivot lever via a cardan shaft. That cardan shaft has to ensure angular compensation in the articulations and longitudinal axial compensation in the intermediate shaft. The angular compensation necessary in the cardan shafts results in various displacement angles in the illustrated drive configuration. That drive configuration thereby has the disadvantage that the rotational movement is not transmitted homokinetically, which again results in undesirable vibrations in the system.